1. Field of the Invention
This invention relates to an improved process for making a stable, reinforced simulated marble or onyx product as well as the product per se.
2. Prior Art
In order to make a simulated marble or onyx product, various methods have been devised for creating the veining or striations in a resin matrix so as to achieve an appearance similar to that of real marble or onyx. Perhaps one of the oldest methods of creating a "marble look" is similar to that of baking a marble cake. In both situations, a colorant is added to a binder material (flour in one instance and resin in the other). By only stirring the colorant a limited extent, striations of color are generated throughout the binder. When the product is finished, an appearance similar to that of marble is achieved.
Synthetic or simulated marble and onyx products are well recognized in the prior art. These products are usually cast so as to form washbasins, countertops and the like. There have been attempts to use the prior art processes for making larger structures, such as, for example, bathtubs, hot tubs, etc., but they have not proved to be successful. One problem with large structures made by the prior art processes is that they are extremely heavy and thus extremely difficult to transport. Further, the large quantity of resin required to make such a structure substantially increased the price. Another disadvantage associated with large structures made under the prior art processes was that they were temperature sensitive. This can lead to shattering, warpage or other problems under certain conditions.
One prior art teaching for making simulated onyx is shown in U.S. Pat. No. 3,396,067. In that patent, opaque filler is embedded in a cast, transparent thermoset polyester copolymer resin. The polyester resin is filled with well-known fillers, glass firt, silica, etc., which have the same index of refraction as the resin. U.S. Pat. No. 3,328,499 shows a similar casting method for making similar products. In another prior art teaching, U.S. Pat. No. 3,773,886, a process is disclosed wherein various layers are utilized so as to achieve a simulated or cultured marble appearance. In order to achieve the striations in the '886 patent, a mixture which includes a rubbery polymeric material producing elongated striations is utilized.
Other prior art processes for making simulated marble and the like are disclosed in U.S. Pat. Nos. 3,370,114; 3,394,021; and 3,434,911.
These references all relate to processes which have a number of shortcomings. Thus, there has been a long felt need for a process which is relatively straight forward and which could be used to make even large structures having a simulated marble or onyx appearance.
The present invention enables even large structures, such as bathtubs, to be manufactured, but does so in such a manner that problems of shattering, warpage and the like are overcome. In addition, the product of the present invention does not use as much resin as associated with the prior art products. These and other advantages are achieved by Applicant's process which produces a completely different cross-section so as to achieve a high strength-to-weight ratio. These advantages are achieved without sacrificing the veining or striations in the product. In addition, the process of the present invention utilizes compositions which can be spray applied obviating the prior art process of casting.